Title: Brightness variations in totally-eclipsing binary GSC4589-2999 Authors: E. Sipahi, H. A. Dal, O. Özdarcan
We present multi-colour CCD photometry of GSC4589-2999 obtained in 2008 and 2009. The observations indicate that the system is an active Algol binary. Based on the new data, the mean brightness of the system is decreasing through the years 2007-2009. The light curves obtained in 2008-2009 are modelled using the Wilson-Devinney code. We also discussed the light and colour variations of the system at different orbital phases. Evidence suggests that these brightness and colour variations are due to the rotation of unevenly distributed starspots on two components of the system.